Post-earthquake performance indicators for sewerage systems

This paper presents a set of performance indicators (PIs) for assessing loss of wastewater service and the induced functional impacts in three different phases: emergency response, short-term recovery and long-term restoration. Built on the experience and learning of the Stronger Christchurch Infrastructure Rebuild Team in reinstating the resilience of the Christchurch wastewater system following the Canterbury Earthquakes in 2010-2011, the developed PIs aim to evaluate holistically the structural, hydraulic, environmental, social and economic consequences that might arise due to the earthquake-induced physical damage to sewerage components. This includes sewer pipelines, pumping stations, manholes and council-owned laterals. Furthermore, a framework in which the proposed PIs are integrated into is introduced for demonstrating practical applications. The decision support framework includes three modules, namely: (a) physical damage module, (b) functional impact module and (c) serviceability restoration module. The framework is intended to support the decision-making process in terms of restoration strategy selection and resource allocation in the move towards an effective and informed reinstatement of sewerage systems after earthquakes.